NEED OPINIONS - Would you be mad/hurt?

So let's start off by saying that I do not believe my partner is doing anything terrible behind my back. He is however keeping things from me and going out of his way to lie.

My partner has always been a very secretive person and hates when people get into his business. He won't talk to me in detail about his money or loans or anything like that. We have been together for 2 years and have a daughter together. We recently moved out into our own rental a couple months ago.

It started off when he started receiving letters and wouldn't open them in front of me and would rip them up before I could see them. He would tell me they are to do with his loans and they are none of my business. Today he received another one and I wanted to see if I was reading into it too much or he was purposely not letting me see AT ALL. We were sitting in the lounge when he saw the letter and held it to the light to see if he could read what he was. He said he couldn't be bothered opening it so he left it. He took it to the kitchen (our house is extremely small so the lounge and kitchen are pretty much the only main rooms in the house) and came back sat with me and I asked where he put it and he claimed he put it on the bench. By this time I was done beating around the bush and went to find it and it had vanished. Like there was no where it could have gone unless he tried hiding it.

Couple hours go by and I went to bed with my daughter and I was texting him and asked if he had read the letter and he said yes and that he found it under the TV (he never even went near the TV). I asked what it was and he replied with it was just for his loan. When he had a shower I got up and saw it ripped up in the bin so I read it and everything was there accept this one info bit stating what the loan was for. I asked when he came to bed and said it was just a loan and the other bit must have fallen deeper into the bin. I let it go.

Another hour passed and I get up to go to the toilet and sure enough in the toilet is the one bit of paper stating what the loan was for. Turns out he just refinanced something, yes it would have been nice if he told me and spoke to me about it first since we are in a relationship but i wasn't really fussed about it at all. I asked him about the paper and he straight out said it was toilet paper and not that piece and when I told him I saw it because the writing was face up he starts GOING OFF saying I'm disgusting because I must have put my hand in the toilet and I'm just desperate to be in his business and I'm a child who wouldn't understand it anyway and eventually told me to F off. Somewhere in this argument he stated that he was testing me and wanted to see what I would say about the so called "toilet paper".

I'm so angry that he can talk to me that way and that he can lie to me so easily over and over again. I wouldn't have even cared if he just told me in the first place like why lie?

Im really starting to believe he doesn't see us as equals since he always calls me a child and says I won't understand just because I haven't taken out a loan or done the same things he has done.

Am I overreacting?

Should I not be considered in financial decisions?

Would you lose trust if your partner did this?

Sorry for the long post